Replace Flex+Bison based zone parser with simdzone

[k0ekk0ek]

There's still some warnings to fix and of course more tests to run. I only did very minor testing yet for NSD integration, but it's a good time to start the review as it's quite a bit (I think). This PR remove the Bison+Flex based zone parser from NSD and replaces it with simdzone.

Please note that both these changes and the current main branch of simdzone require review. This is also a good time to figure out how to best manage sub modules in the NSD repository. I now just did it commit based on the latest commit in master, we probably want to change that?